1. Field of the Art
The disclosure relates to the field of multimedia consumption, and more particularly to the field of broadcasting multimedia content to mobile receiver devices.
2. Discussion of the State of the Art
Today there are many mobile devices such as multimedia players, smartphones, tablet computers, or other various mobile electronic devices, that have the ability to play media to a wireless playback device (such as a speaker, stereo receiver, or television) over a radio-based wireless link such as BLUETOOTH™ or WiFi wireless data transmission protocols. If the user desires to split the media playback, for example to broadcast a video content stream to one receiver (such as a television) and a corresponding audio stream to a separate receiver (such as a pair of headphones, so as to not disturb others nearby while viewing media content), no such system is available.
What is needed, is a system to take a plurality of media content streams, and enable broadcasting of each stream or of portions of a single stream to separate receiver devices, while keeping the delay between the rendering of these streams (latency) low and maintaining synchronized playback of these streams so as not to degrade the quality of the experience. So for example if a video content stream is sent to a TV and an audio content stream is sent to wireless headphones (for example), the audio media that corresponds to the video must not be too delayed with respect to the video (defined in the art as latency), to a degree that a user might notice this delay and thereby degrading the users media experience. Furthermore if two or more users are listening to audio content, it may be desirable that the rendering of this content is synchronous, so that all users experience the audio at the same time.
A very specific desirable application may be that of a WiFi enabled “smart” TV, or WiFi set top box that may present video media content to a television while simultaneously sending audio content wirelessly over a WiFi network to one or more smartphones that may be used by users watching the TV screen. The smartphones may then play the audio content received wirelessly over the WiFi network through ear buds (or similar audio playback hardware) that a user is using.
Such an arrangement allows a user to experience the video component of the media on the TV and the audio component of the media through their smartphone and therefore not disturb other occupants in the room. For this experience to be effective the media must be transported over a wireless network such as a WiFi network, which is generally built into smartphones (and other personal media devices in the art, such as music players, tablet computing devices, or other suitable portable electronic devices) as an integral hardware feature, the latency of the audio component played via the smartphone must be low with respect to the video component played on the TV (so as not to degrade the user experience as described above) and if multiple users are watching the TV video content, all audio components being played must be time synchronized such that the playback experience is similar for each individual user. Low latency transport of media over WiFi and media playback synchronization over WiFi presents many challenges that the invention aims to solve, as described herein.